The district attorney's office said Lowell police responded to two 911 calls. The first call was from a woman reporting that an out-of-control armed man was threatening to kill people. The second call came from a man, identified as 39-year-old Jose Perez, saying he was going to kill everyone and requesting police officers be sent.

According to the district attorney's office, when officers arrived at the scene, they encountered Perez, armed with a meat cleaver and another large knife.

Police said Perez ignored their orders to drop his weapons and approached them while armed.

According to the DA's office, the police officers fired their guns, hitting Perez.

Perez was transported to Lowell General Hospital where he was pronounced dead.

Both officers have been placed on administrative leave pending the results of the investigation.

The Middlesex District Attorney's Office and the Lowell Police Department are investigating.